RRH selection and UE transmission time adjustment for LTE-advanced uplink MU-MIMO in Distributed Antenna System environment

In this paper, after we investigate the influence of the arriving time difference on LTE-Advanced uplink MU-MIMO in Distributed Antenna System (DAS) environment, we suggest RRH selection and transmission time adjustment method for obtaining the receiving performance gain. DAS which is one of CoMP technologies has known as the most efficient technology for improving spectral efficiency and cell-edge user throughput. However, when uplink MU-MIMO is carried out in the DAS environment, the arriving time difference is inevitable owing to geographical distribution of RRHs location. The arriving time difference of the multiple UEs has decisive effect on system performance. Therefore, in this paper, we propose RRH selection and UE transmission time adjustment method for minimizing the arriving time difference. Through link-level simulation, we show the impact of the arriving time difference on LTE-Advanced uplink MU-MIMO in DAS environment and compare the performance of the suggested method with that of the conventional method.